The sixth body was retrieved at 11:00 p.m. Saturday, said Gao Minhui, a member of the rescue headquarters.

The official also predicted a slim survival chance for the two missing.

So far, the rescue operation was going slowly due to complicated situation underground, said Gao.

The flooding occurred Thursday afternoon in Ping'an Coal Mine in the coal-rich city of Fuxin when ten miners were working underground.

Two miners were rescued out of the pit Friday. They were being treated in a local hospital and were out of danger, hospital sources said.

Preliminary investigations showed that water in an old abandoned tunnel suddenly burst into the new-developed tunnels in the coal mine, and as a result, several small tunnels were blocked by sand and rocks washed there by the floodwater.

More than 160 rescuers divided into four groups are working on rotation and round-the-clock to rescue trapped miners. They went down the shaft to clear the blocked tunnels Friday afternoon, Gao said.

Rescuers have to transport the sand and rocks out of the shaft before reaching the trapped miners but due to the narrow tunnel, the clean-up work was going on slowly, Gao added.

"So long as there is hope, we'll not stop our rescue efforts," Gao said.

The compensation work also started on Sunday and families of each miner will be paid at least 200,000 yuan (about 25,000 U.S. dollars), said the official.

Over the past two weeks, at least 126 miners were killed in mine incidents in China and investigations have shown that most of the incidents occurred as the mine owners violated safety regulations and illegal production.